Dynamo-electric machine



E. PAWOETT.

I DYNAMO ELECTRIC MACHINE.

Patented 001;. 16, 1894'.

MW WM UNITED STATES PATENT OFFICE.

EZRA FAWOETT, OF ALLIANCE, ASSIGNOR OF ONE-HALF TO LEONARD WV.

BRADLEY, OF CLEVELAND, OHIO.

DYNAMO-ELECTRIC MACHINE.

SPECIFICATION forming part of Letters Patent No. 527,415, dated. October16, 1894.

Application filed February 15, 189A. $erial No. 500.196. (N0 model.)

To aZZ whom it may concern.-

Be it known that I, EZRA FAWGETT, a citizen of the United States,residing at Alliance, in the county of Stark, State of Ohio, haveinvented certain new and useful Improvements in Dynamos, of which thefollowing, with the accompanying drawings, is a specification.

The object of my invention is an improved connection between the coresor field pieces and the pole-pieces of electro-magnets for d ynamos andelectric motors whereby a perfect connection is made and the greatestpossible contact secured between said parts, with extreme simplicity ofconstruction and ease of assembling the parts of such machines.

My invention consists in the details of construction described hereinand defined in the claims.

In the drawings, Figure 1 is a vertical sec tion of a dynamoillustrating the application of my invention to one form of that classof machines, and Fig. 2 is a vertical section of a dynamo illustratingthe application of my invention to another form of that class ofmachines. Fig. 3 is a cross-section of the core and coil on the line a:as. The application of my invention to the two forms of dynamosillustrated is given to show the universal adaptability of theinvention.

In Fig. 1 of the drawings, two forms of construction are illustrated,both of which will be readily understood from the drawings and astatement of the different parts of the dynamo illustrated. 1 is apole-piece, 2 is a core, 3 is the base or heel piece, and 4 is the coilthat is wound around the core 2. In this side of the dynamo thepole-piece 1 and the core 2 are separate pieces joined by my improvedconnection. In the opposite side of the dynamo illustrated by Fig. 1,the polepiece 5 and the core 5 are integral, the core 5 being joined tothe base or heel 3 by my improved connection.

4 is the coil that is wound upon the core 5.

6 is the armature of the dynamo illustrated by Fig. 1.

In Fig. 2 the pole-pieces 7 and 8 are intogral with the base pieces 7and 8 The core To insure a perfect connection with the greatest possiblecontact of surface between the cores or field pieces and the pole piecesand the base, I provide the cores 2, 5 and 2 with tapering ends 2- and 25 and 2 and 2; and in the pole piece 1, base 3, and pole pieces 7 and 8,I form tapering openings 1, 3 and 3 and 7 and 8 of the same slant as thetapered ends of the cores and adapted to receive the tapered ends of thecores and to make close contact therewith on all sides of the taperedends of the cores. When the pole pieces and the cores are connected asare the pole piece 1 and core 2 of Fig. 1, a screw bolt 9 passes downthrough the pole piece and screws into the end of the core 2, asillustrated. In the other connections, Washers 1O and 10 are placedbelow the base 3, and washers 10 and 10 are placed on the outside of ithe pole pieces 7 and 8. Through these washers pass screw bolts 11, 11,11 and 11 into the ends of the cores, 2, 5 and 2, as illustrated. Thescrewing of the bolts into the ends of the cores as described draws thecores tightly into the tapering openings made to receive them, andinsures a perfect connection with the maximum of meeting surfaces. Inpractice the working efficiency of dynamos is increased fromtwenty-seven to approximately forty per cent. by myimprovement.

What I claim as my invention, and desire to secure by Letters Patent, is

1. The combination, in a dynamo or other electrical machine, of a fieldpiece having a tapering end and a pole piece having a tapering openingto receive the tapering end of the field piece, substantially asdescribed.

2. The combination, in a dynamo or other electrical machine, of a fieldpiece having a tapering end, a pole piece having a tapering opening toreceive the tapering end of field 5 EZRA FAW OETT.

Witnesses:

JOHN TOWNSEND, R; B. FAWCETT.

IOO

